So, I'm learning to use my Lee Prefect Powder measure and pretty much like it a lot. I did the "break in" thing according to the instructions where you run a powder through it to get it "lubricated." Now it seems like the first five or so loads get progressively lighter. I'll start at 7.4 grains and five loads later it is down to 7.1. So I re adjust and it stays pretty consistent for the remainder. I'm checking the weight every five or ten loads. Anybody else run into this?

Right tapping is the key. Start with the handle in the UP position. Bring the handle down and give two firm taps at the base of the handle, get the case under the spout and bring the handle up, then before removing the case give two more firm taps.... Also do keep the hopper at least 2/3 full at all times....

Thanks. I am starting to think that it is my scale that is at fault. I'm using an electronic Hornady scale. I suspect it it too susceptible to conditions. Thinking maybe I need to look into getting a balance type scale.

Ah.... That could be a problem. where are you loading? climate controlled or a garage/shed? Big temp changes will mess with a scale, like turning on a heater or AC when you go in to reload, or bringing the scale from inside to a garage/shed with a big temp difference... You want to let it acclimate to a stable temp for 30 min if thats the case. You also want to make sure no fans or hvac is blowing on it, that would mess with a beam scale too....

Lees beam scale can be difficult to use, but once you get it down, its very accurate and at a reasonable price. I trust my lee beam scale over my electronic any day. If they ever do not agree, I calibrate my electric, and just like that, they agree...

When working up loads, the electric is easier to use, but when working with a known weight once the load workup is done, I always use the beam scale.

at the top and bottom of each pull I give mine a double tap on the front of the drum. Also when Im first dialing in a specific measure, I always run 3-4 throws first then take the next one and check my weight then re-adjust if needed. mine has been very consistent. oh yeah, my first rookie mistake was not having the hopper lined up correctly and on the upstroke the lever was hitting the side of the hopper

Consistency is crucial to using the PPM. With or without the tapping, each load thrown should involve the same pattern & timing. I sometimes find myself literally counting out a rhythm to the sequence. It also helps to add a baffle at the bottom of the hopper to keep the powder weight pressing into the discharge area more consistent. Aluminum from a soda can works fine & can be cut to shape with scissors then bent to fit.

With fine powder, like H110, I frequently see consistent drops that look to be within 0.02 grains of the target amount when not dead on. After getting the drop dialed in, I'll check every tenth round or so to double check that things are staying on target.

I find larger extruded powder, like IMR 4895, more problematic, with variations between throws sometimes a tenth of a grain or more, probably due to variability in the density of a given drop. I generally end up throwing a somewhat lighter amount than desired & trickle to the full amount.

I use a lee safety scale for weight checking, using the poise lock for the target amount. I added plus/minus 0.1 and 0.2 grain reference marks above/below the balance point mark & it is pretty easy to interpolate to roughly 0.01 grain variations when checking throws.

Some less expensive electronic scales cannot hit all the 0.1 grain measures & will "skip" some 0.1 levels (i.e. jump from 0.2 to 0.4 for example). They are typically accurate to 0.01 gram & convert that to get grains. Rounding error results in the skipped 0.1 grain values.

This email link is to reach site administrators for assistance, if you cannot access TFL via other means. If you are a TFL member and can access TFL, please do not use this link; instead, use the forums (like Questions, Suggestions, and Tech Support) or PM an appropriate mod or admin.

If you are experiencing difficulties posting in the Buy/Sell/Trade subforums of TFL, please read the "sticky" announcement threads at the top of the applicable subforum. If you still feel you are qualified to post in those subforums, please contact "Shane Tuttle" (the mod for that portion of TFL) via Private Message for assistance.

This email contact address is not an "Ask the Firearms Expert" service. Such emails will be ignored. If you have a firearm related question, please register and post it on the forums.